将float数字按照一定格式写入到文件中

/*
float.c
*/
#include<stdio.h>
#include<string.h>

int main()
{

    FILE *fp = fopen("Data.txt","w+");
    float f[][] = {{-3.41, 5.63, , 7.8, 1.3},
        {4.5 , -, -23.5, , -23.794},
        {-12.5, -96.2, -8347.2, , -629.0},
    };

    char buf[];
    int offset = ;
    int i,j;
    for (j =  ; j < ; j++)
    {
        offset = ;
        for (i =  ; i < ; i++)
        {
            offset += sprintf(buf+offset, "%.2f ", f[j][i]);
        }
        sprintf(buf + offset,"\n");
        printf("%s",buf);
        fwrite(buf, strlen(buf), , fp);
    }
    fclose(fp);
    return ;
}